Chapter 17 Fire Control Flashcards
In order of importance, three priorities
Life safety
Incident stabilization
Property conservation
Offensive factors
Value
Time
Size
Defensive if:
No threat to occupant life Occupants aren’t savable Property isn’t salvageable Lack of resources Risk of collapse Anything that endangers lives
Three priorities
Life safety, incident stabilization, property conservation
Offensive strategy considerations
Value - saving lives or property
Time - Is there enough time, will conditions change, building collapse etc
Size - Are there people and equipment/water resources available
Defensive strategy
Can’t save anyone or building, lack of resources, danger of collapse, unfavourable wind conditions
Intended to isolate incident, keep it from expanding
Generally exterior
OHSA has two in two out regulation
Transitions
More common less dangerous is defensive to offensive
Offensive to defensive usually from rapid change in conditions
Offensive to defensive requires PAR
Don’t abandon hose line unless absolutely necessary (during tactical withdrawal)
RIT should be prepared to help people withdraw
Small diameter hoseline SDH
3/4 inch to 2 inches or 20-50mm
Backup hoseline
Must be placed at same time as primary. Should be same size as primary. Should be fog nozzle for protection with cone if needed
Backup serves to
Protect attack hoseline from extreme fire behaviour
Protect means of egress
Provide additional suppression capability if needed
Textbook says fog nozzle in general is the best
Entering
Make sure you have TIC, tools, charged line with pattern checked and air bled
Watch for smoke out air in
Check for heat with TIC hand or spraying water on door
Open door slightly, spray and wait 5-10 seconds to see what happens
Have rope or something on the door to close quickly if needed
Attacking from unburned side
Thoroughly disproved
Greater heat release rates of modern buildings with increased effect from wind on fire expansion and development
Attack with wind at your back
Direct attack
Directly on to burning fuel or onto ceilings and walls
Don’t use so much it drops thermal layer
Indirect attack
Made from the outside
It makes floor to ceiling one temp
Aim at ceiling with fog stream
Combination
Make a Z O or T shape with nozzle attacking fire and ceiling
Shielded fire
You cannot see from the doorway because it is located in a remote part of the structure
Use gas cooling - short bursts of water fog into gas layer, stops pyrolysis and what not. Length of pulse depends on size of space. You want to cool gas itself not the ceiling
Upper level fires
Newer buildings typically have protected standpipe
If not protected start one floor below to hook up
If using elevator, typically only 2 floors below fire as staging area
Watch for overhead risks like fallings debris and glass
Evac and hauling equipment in high rises can be resource heavy
Residential basements
Unfinished floor joists will fail sooner
Drop in tiles add minimal fire resistance and add to fuel load
Lightweight construction materials prone to collapse possible
Sounding and TIC are not sufficient to ensure integrity
Enclosed stairwells act as a chimney for heat and smoke
Need enough hoseline plus 6-8 feet
Jet fuel must burn less than
538C
Exposure
Any unaffected area
Interior protection is closing doors and using ventilation, passive forms are fire rated walls and doors
Exterior exposure protection is typically wetting buildings/moving anything out of the way
Utilities
Never turn them back on
Never remove meter box
Only meter box shutoff can shut off all power
Never touch service mast (pole that connects power to building) in older buildings fuses would blow connecting wires to mast
If backup generator is in building then main box won’t necessarily cut all power
Solar panels are always charged
High low voltage
High excess of 600 volts
Low less than 600, usually 120 or less
Natural gas
Pure form is methane with flammability range of 5-15 percent is nontoxic
Natural gas lighter than air, also nontoxic but is an asphyxiant
Mercaptan added
Some emergency generators run off natural gas
Meter can be inside or outside
1/4 turn tang
LPG
butane and propane (plus others)
Propane also has no odour, mercaptan added, nontoxic asphyxiant
1.5-10 percent for explosive concentration
LPG leaks will give visible cloud the hugs ground - fog stream of 400lpm will dissipate this cloud
Water connections
1/4 turn tang
Electrical ground may be connected to water pipes
May need special tool for commercial
Sprinkler control valves are electronically monitored or physically secured shut
Never shut off sprinklers until fire under control and IC says so
Class C fires
Turn off power, then they are class A or B. Sometimes extinguish themselves with power cut. Lockout/tagout so power doesn’t get turned back on.
If water MUST be used, fog or spray stream
Greater than 40 volts is potentially dangerous
Dry chem may wreck equipment - halotron instead
Master stream
Gotta shut it off to move the whole thing so position carefully
Aim so its angled at roof and deflects off
Big fires position it so it can be adjusted without moving to hit large amounts of building
Most effective exposure prevention is wetting the building itself, if can’t cuz its something like a bunch of trees water curtain works. Needs compact water droplets to stop radiant heat
Transformers
Older ones contain polychlorinated biphenyls (PCBs). Assume they all do (carcinogenic and flammable). Even if labeled it doesn’t have any, can have up to 49ppm.
Use dry chem or CO2 for ground level transformers.
Allow pole top transformers to burn, let utility company knock it out with dry chem from aerial - may consider extinguishing pole itself to prevent it from falling
Class C fires
Turn off power, then they are class A or B. Sometimes extinguish themselves with power cut. Lockout/tagout so power doesn’t get turned back on.
Commercial high voltage
Don’t use water even with fog cuz of damage to equipment
Search with back of hand to avoid grabbing and sticking to something if electrocuted
Transformers
Older ones contain polychlorinated biphenyls (PCBs). Assume they all do (carcinogenic and flammable). Even if labeled it doesn’t have any, can have up to 49ppm.
Use dry chem or CO2 for ground level transformers.
Allow pole top transformers to burn, let utility company knock it out with dry chem from aerial - may consider extinguishing pole itself to prevent it from falling
Underground transmission lines
stay 300ft 91m away
Backdraft conditions high in underground vaults
Commercial high voltage
Don’t use water even with fog cuz of damage to equipment
Search with back of hand to avoid grabbing and sticking to something if electrocuted
Guidelines to electrical emergencies
Short circuit could have weakened other lines which may fall
Use approved tools with insulated handles
Wait for power to be cut
10ft away from overhead lines raising equipment
Fog streams with at least 700kPa
May need to be up to 150ft away from downed powerlines
Shuffle or hop
NFPA 1971
Standard on protective ensembles for structural firefighting and proximity fire fighting
Passenger compartment fire
If need to get in break window
Use medium fog
Fire vehicle attack
45 degree angle to avoid exploding shit
Hoseline between exposures and vehicle
All clear when occupants out
Passenger compartment first then ground then exposures
Minimum 360lpm
If metal itself is on fire use class D, water fine if not.
Car engine fires
hose stream through grill or hood scoop
Penetrating nozzle through hood fenders or wheel wells
Passenger compartment fire
If need to get in break window
Use medium fog
Alternative fuel vehicles
Badging to identify what fuel is not necessary
Park apparutus 30m away min
Approach from uphill upwind 45 degree angle
Do not use flares? Lol dumb textbook
Natural gas cars
CNG - compressed natural gas
Burns clean, high-ignition temp, narrow explosive range, nontoxic noncorrosive lighter than air stored under pressure
Government, utility, refuse, busses most likely to be CNG or LNG (liquified natural gas)
May have fuel tank shutoff, fuel tanks will splode
Consider allowing fuel to burn itself down
LNG stored at -162C
Frost on tank of LNG indicates tank failure
LNG use purple k or high expansion foam and sand or dirt to stop it entering drains
LPG liquified petroleum gas cars
Most common after gas and diesel Also no odor Stored under pressure Expands 1.5X for every 10 degrees increase in temp Can BLEVE because of this Cool top of tank
Hydrogen cars
4-75% flammability range Self ignites at 287.7C Invisible flame during the day Vented fuel cell in the trunk C-posts contain vents - don't cut in extrication Don't extinguish this
Ethanol/methanol
Water soluble, electrically conductive with slight gas odor
Burn bright blue and may not be able to see in daytime
50% of gas is ethanol blend in US
Need AR foam such as AR AFFF
Request hazmat for fire or leak
Biodiesel
Blend from natural plants and diesel
Yellow liquid odour of cooking oil
Flash point 130C
Use dry chem CO2 water fog or foam
Clandestine drug labs
Bad chemicals
Booby traps
Weird wiring - often illegaly tapped into nearby buildings
Three main infuelnces on ground cover fire behaviour
Fuel, weather, topography - weather most significant
Names of ground cover fire
Origin is… the origin
Head is the fastest growing part - usually in direction wind is blowing - usually key is attacking head and preventing new heads
Fingers are narrow long strips extending from main fire - can form new heads - typically light fuel
Heel - fire side opposite head, usually against the win and downhill and easy to control
Islands - patches of unburnt fuel inside perimeter
Topography
Burn faster uphill
Faster on southern exposures (in northern hemisphere due to sunlight)
Steep ravines can cause turbulent updrafts creating a chimney effect, fires in these areas can grow extremely fast
Names of ground cover fire
Origin is… the origin
Head is the fastest growing part - usually in direction wind is blowing - usually key is attacking head and preventing new heads
Fingers are narrow long strips extending from main fire - can form new heads - typically light fuel
Heel - fire side opposite head, usually against the win and downhill and easy to control
Islands - patches of unburnt fuel inside perimeter
NFPA 1977
Wildland firefighting
NFPA 1500
Fire department OH and S For ground cover fire states Helmet with eye protection and neck shroud Flame retardant shirt pants or jumpsuit Sturdy boots WITHOUT steel toes Gloves Fire shelter in crush resistant case
Fusee
A friction match with a large head capable of burning in the wind
Non fire wildand hazards
Unstable trees, animals, insects, electrified fences, power lines, explosives, haz mat, rolling or falling debris, pits or shafts, animal traps
Heart failure # 1 cause of death in wildland
RECEO-VS
Rescue Exposures Confinement Extinguishment Overhaul Ventilation Salvage
Incident priorities for any emergency
Life safety
Incident stabilization
Property conservation
RECEO-VS
Rescue Exposures Confinement Extinguishment Overhaul Ventilation Salvage
Typical search priorities
Most severely threatened
Area with largest number threatened
Remainder of fire area
Exposures
Blitz attack
Aggresively attack a fire from exterior with large diameter (65mm or bigger) fire stream
Typical search priorities
Most severely threatened
Area with largest number threatened
Remainder of fire area
Exposures
Underground spaces
All equipment needs to be intrinically safe for use in flammable atmospheres O2 deficiences Flammable and toxic gasses Temp extremes Explosive dust Limited means of entry and egress Cave ins or unstable support members Standing water or other liquids Utility hazards Increased heat means more O2 consumption and faster fatigue
Flash point
Under 38C is flammable (gas and acetone) over is combustible (kerosene vege oil)
Further divided into hydrocarbons (dont mix with water) and polar solvents) do mix with water
Underground spaces
All equipment needs to be intrinically safe for use in flammable atmospheres O2 deficiences Flammable and toxic gasses Temp extremes Explosive dust Limited means of entry and egress Cave ins or unstable support members Standing water or other liquids Utility hazards Increased heat means more O2 consumption and faster fatigue
Flash point
Under 38C is flammable over is combustible
Liquid fires
Dont step in pool of it
Unburned vapours usually heavier than air and form pools or pockets of gas in low areas
Consider all ignition sources (tools vehicles smoking materials electrical fixtures)
Assume relief valve cannot keep up to extreme temps
Foam is most common method to extinguish
Water for class B
Not good for lighter petroleum or alcohols
Okay for heavier oils like raw crude
Above level of contained liquid for cooling
Can use water to move liquid fires and vapours
2000LPM per flame impingenment on tanks (solid stream)
If need to advance have a backupline with separate water source and pump
Non water based
Coal plants, aircraft hangars, and large cargo vessels
Can be CO2, clean agent, dry and wet chem
Must wear SCBA
Have a hoseline
Water for class B
Not good for lighter petroleum or alcohols
Okay for heavier oils like raw crude
Above level of contained liquid for cooling
Can use water to move liquid fires and vapours
2000LPM per flame impingenment on tanks (solid stream)
If need to advance have a backupline with separate water source and pump
Transport fires
Wheels may fail and cause fuel to shift
Careful of traffic
Limited water supply
Gas pipes
Presures range from 7000 kPa to 2 kPa
Usually below 350kPa in local distribution piping
Liquid natrual gas is subject to BLEVE
Protect exposures, shut off gas, do not extinguish
